Simple voltage shunt circuit to balance LFP cells. R8 and R9 sets shunting threshold to 3.45V and placed away from heat generating parts to reduce voltage drift. Shunting current should be around 0.38A should be enough to keep 100A cells in balance. Single sided PCB no holes or vias, easy to etch yourself with toner transfer method. I plan to clip these directly onto cell terminals using alligator clips. Edit: Transistor T3 is BSP43 1A NPN.
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